Method of making ferrite matrices

ABSTRACT

A method of making ferrite matrices comprises the steps of threading a plurality of ferrite cores, arranged into stacks, about at least one wire, the number of the cores about the wire being equal to the number of the lines in a matrix to be made; arranging the stacks into a row in which the number of the stacks equals the number of the wires in the direction of one coordinate of the matrix to be made; separating one core from preferably each one of the stacks; arranging the separated ferrite cores in a plane intersecting the wires; winding an additional wire into a helix; rotating the helix and forwarding the same; threading the additional wire wound into this helix in the direction of the other coordinate of the matrix to be made, so that the leading end of the helix passes in succession through all the ferrite cores arranged in the said plane, whereby at least one core is received about at least one turn of the helix; straightening the additional wire, whereby the ferrite cores received thereabout become positioned at the intersections of the wires, each core being indexed in a desired angular position. The invention can be employed for making ferrite matrices with any desired arrangement of the cores at the intersections of the wires, as well as for making ferrite cubes in the form of carpets, plaits, frameless memory devices of practically unlimited capacity, with cores of any size, including the tiniest ones.

[ Jan.7, 1975 United States Patent Selezney et a1.

[ METHOD OF MAKING FERRITE [57] ABSTRACT A method of making ferritematrices comprises the MATRICES [76] Inventors: Jury EmelyanovichSeleznev,

Vesenny P 16; l steps of threading a plurality of ferrite cores,arranged Alexandmv'ch Burkm, Ts vemol into stacks, about at least onewire, the number of the 24; S cores about the wire being equal to thenumber of the vladlmutovlch Kuzmm, uhtsa lines in a matrix to be made;arranging the stacks into Akadeymlcheskayai an of a row in which thenumber of the stacks equals the Novoslbu'ski number of the wires in thedirection of one coordinate 22 Filed; 27 1972 of the matrix to be made;separating one core from preferably each one of the stacks; arrangingthe sepa- PP bio-13194353 rated ferrite cores in a plane intersectingthe wires; winding an additional wire into a helix; rotating the helixand forwarding the same; threading the additional wire wound into thishelix in the direction of the other coordinate of the matrix to be made,so that the [52] US. 29/604, 29/203 MM, 29/241 leading end of the helixpasses in succession through all the ferrite cores arranged in the saidplane, whereby at least one core is received about at least 6 34 N32 74M mm H ,9 s "M0 m m3 0A m M M4 0 M "9 m m U 5 c4 mw "so an 1 nw e hF U00 55 one turn of the helix; straightening the additional w|re, wherebythe ferrite cores received thereabout become positioned at theintersections of the wires, each core being indexed in a desired angularposition. The invention can be employed for making ferrite matrices withany desired arrangement of the cores at the intersections of the wires,as well as for making ferrite cubes in the form of carpets, plaits,frameless memory devices of practically unlimited capacity, with coresof any size, including the tiniest ones.

4 Claims, 13 Drawing Figures 4 44 WO OO 6M66 49 99 72 22 H H O u .9 M mm N u m m d "nun" e A m P Nun" 3 m ml ha C a S t s H E n e fl a mT nmumiE .D fe mm anmmu w .NSKLSSH m E34579 r 66666 6 1.99999 lllll ni OSZMW m.U a l ax E 33855 l mumm mm 64800 t .1. 036 6 M 6 11.1 4 n t 3 3 3 3 3PA Attorney, Agent, or Firm-Holman & Stern Pmm'od Jan. 7, 1915 ,858,310

9 Sheets-Sheet 1 Patented Jan. 7, 1975 9 Sheets-Sheet 2 9 Sheets-Sheet 5Hlll Patented Jan. 7, 1975 3,858,310

9 Sheets-Sheet 4 FILlb Patente Jan. 7, 1975 9 Sheets-Sheet 5 PatentedJan. 7, '1975 9 Sheets-Sheet 6 FIEJO Patehted Jan. 7, 1975 9Sheets-Sheet '7 FIE. 11

Patented Jan. 7, 1975 9 Sheets-Sheet 8 Patented Jan. 7, 1975 3,858,310

9 Sheets-Sheet 9 METHOD OF MAKING FERRITE MATRICES BACKGROUND OF THEINVENTION The invention relates generally to processes of making memorydevices including ferrite cores, for the memories of electroniccomputers, for logic automatic apparatus, for control and communicationcircuits, monitoring systems and more particularly, it relates tomethods of production of ferrite matrices and cubes and to apparatus forperforming such methods.

The invention can be employed for the production of ferrite matriceswith any desired disposition of the cores at the intersections of thewires in a matrix, as well as for the production of ferrite cubes in theform of carpets, plaits, frameless storage devices of practically anycapacity from cores of any size, super-mini cores included.

There are known various methods of making ferrite matrices. One of themcomprises the steps of first putting the ferrite cores about the wiresextending along one of the coordinates in stacks, then mounting thesewires parallel to one another in an array onto a framework, the numberof the wires and the number of the cores about each wire corresponding,respectively, to the number of the columns and lines in the matrix to bemade.

Then one core is separated from each stack, and the cores are indexed ina desired direction, i.e., each core is positioned at 45 angular degreesin respect of the wire, in either direction, in accordance with thepredetermined threading pattern. Thus indexed, the cores are arrangedinto a row, and a needle is threaded therethrough in the direction ofthe second coordinate, the needle dragging thereafter a mounting wire,in which way a line of the ferrite matrix is made.

The threading of the cores is continued in the same manner, line byline, and, after the coordinate grid has been completed, thereadout-inhibition windings are threaded through.

This method is practiced nowadays as a widely popular manual techniqueof making ferrite matrices.

The disadvantages of this known method are the difficulty of threadingthrough a line with a needle, on account of the eyelet in each corebeing diminished by the turned position of the core; the difficulty ofbuttsoldering the wire to the needle and of subsequent finishing of thesoldered joint; the evantuality of harming the cores and the insulationof the mounting wire with the steel needle, particularly, by the pointedend thereof and by the soldered joint; the complications encountered atattempts to mechanize this manual process embracing separation andindexing of the cores, arranging them in the threading zone; and,finally, the fact that it is virtually impossible to introducemechanization in this manual process in the case of super-mini cores.

Based on the above-described known method, as applied in the case ofrelatively large cores having the external diameter above 1 mm, therehas been developed an apparatus introducing mechanization into theprocess of the threading ferrite matrices. This known apparatuscomprises a framework on which an array of wires having the cores putthereabout is mounted. Extending transversely of the wires is a coreseparating member in the form of a plurality of contoured combs, ofwhich one retains the stacks of the cores, while the other one, spacedfrom the first one by a spacer corresponding to the height of the cores,separates by its sharp edge one core from the stack on each wire,whereafter the first comb is driven clear of the separated cores, andthey slide down the respective wires. Monnted parallel to the separatingmember is an indexing member in the form of contoured toothed stripsturning the cores in desired directions and fixing them in the turnedpositions. The contoured strips have a notch at their division zone,which notch acts as the guiding channel for the needle with thethreading wire, in the area of the eyelets in the cores.

The above-described apparatus is of a complicated structure and involvesthe use of numerous precisionmanufactured parts.

At present, there are employed apparatus for threading ferrite matriceshaving the cores of the external diameter in excess of l mm. Theattempts to create a similar apparatus which would handle cores with theexternal diameter equal to 0.8 mm have so far proved futile. It shouldbe remembered that the present-day technology involves threading ofcores with the external diameter as small as 0.3 mm to 0.6 mm, and incertain cases even 0.2 mm.

It is obvious that the core threading operation which so far has been amanual one is bound to become completely automated, if it is to beemployed with cores of extremely small diameters. The operation becomestoo complicated for the skill of a man, whereas the poor productivity ofthe manual operation, considered in the view of the ever growing demandfor ferrite memory devices, makes the automation of this process anoutright economic necessity.

Among the disadvantages of the above-specified known apparatus forthreading comparatively large cores are: insufficient dependability ofseparation of the cores from the stacks, the necessity of employingneedles, with all the complications this necessity involves (e.g.,harming of the cores and of the insulation of the wire, the operation ofpreparing the needle, the eventuality of the wire breaking loose fromthe needle in the course of a line threading operation, manual guidingof the needle into the guideing channel). The employment of positivephysical turning of the cores of small sizes practically always leads tobreaking the cores either partly or completely, greatly strains the eyesof the operator, brings down the productivity of labor; in the case ofsuper-mini cores, as small and as light as dust, the apparatus simplycannot be operated.

There is yet another known method and apparatus for threading ferritematrices, in accordance with which vibration is employed to position thecores in a specially designed mask-holder in the form of a strip withopenings made therethrough, the openings having the outline and the sizeof a core. The openings are situated in the places which the cores areto occupy in the matrix, with the cores turned strictly at 45 in respectof the lines and columns of the matrix, in accordance with a desiredpattern. The mask has a substrate with a tacky layer adhered thereto onone side thereof, so that each opening becomes a cell with a tackybottom to hold a core. The mask is positioned above the cores, with thetacky layer of the mask facing the cores, and the latter, jumpingchaotically under the action of vibration, stick in the cells of themask.

Once positioned in the mask, the cores are threaded through with hollowneedles extending in perpendicular directions, and the coordinate wiresare passed through these needles. Then the tacky layer and the maskitself are removed. In this way, the problem of introducing automationinto some of the processes of making memory matrices has been solved.

This present-day technique, however, is not free from certaindisadvantages: the masks and the needles employed are high-precision,complicated and costly articles. The masks, which are made with a greatdifficulty in the case of minicores, are not completely filled with thecores in the vibratory machine. Placing the cores manually into theunfilled cells of the mask reduces the productivity and results inharming of the mask itself and of the adjacent cores. The hollow needlesfor cores which are by far not the tiniest ones, e.g., those havingdiameters equal to 0.3 mm, 0.17 mm, 0.06 mm, are bound to have theexternal diameter thereof (for threading but two coordinate wiresthrough a core, considering that the core is turned, and the first wireoccupies the space in the eyelet) approximating 60 microns, and theinternal diameter of the needles should provide for the passage of awire not thicker than 40 microns, which is extremely difficult toattain; when the wires are of a considerable length, the process cannotbe performed altogether.

The operation of removal of the tacky layer and of the mask itself fromthe threaded matrix also results in harming of the cores, which furtherbrings down the percentage of acceptable product.

The above technique makes it impossible to perform testing of theelectric properties of the cores and replacement thereof, should a coreprove faulty, directly in the process of threading, until itscompletion, since making good of a detected fault in no way simplifies,but, most certainly, complicates the operation, as compared with thealternative of repairing a ready matrix.

The above technique introduces mechanization into that part of manualoperation which is the most laborconsuming one, even the major one, butmerely a fraction of the entire process of making a ferrite matrix.Numerous operations, including re-filling of the masks, inspection ofthe filled-in masks, assembling them over the full space of a matrix,indexing of the needles for threading, soldering of the inter-matrixconnections of the coordinate wires, repairing of the masks, should acore prove faulty, are still performed manually and greatly strain theeyes of the operator.

The technique makes it possible to do without soldering only in the caseof matrices of small capacities; it is impractical in case of super-minicores having the external diameter below 0.4 mm.

SUMMARY OF THE INVENTION An object of the present invention is toprovide a method of making ferrite matrices and an apparatus forperforming such method, which will make it possible to introduceautomation into the process of threading ferrite matrices of greatcapacities.

Another object of the present invention is to provide an apparatusenabling automatic manufacturing of ferrite matrices made up ofsuper-miniature cores.

Still another object of the present invention is to reduce the number ofsoldered connections of the wires in a ferrite memory cube.

With these and other objects in view, the invention resides in a methodof making ferrite matrices, comprising the steps of putting the ferritecores, the number of which corresponds to the number of the lines of aferrite matrix to be made, arranged in stacks, about at least one wire,arranging the stacks into an array, the number of the stacks being equalto the number of the wires extending along one coordinate direction ofthe matrix to be made, separating preferably from each stack one of thecores, arranging the separated cores into a row and threadingtherethrough at least one additional wire in the direction of the otherone of the coordinates ofthe matrix, thus making one line of the matrix,in which method, in accordance with the invention, the cores separatedfrom the stacks are arranged in a plane intersecting the wires, and saidat least one additional wire to be threaded therethrough in thedirection of the other coordinate is wound into a helix, so that theleading end of the helix, when the latter is rotated and forwardedlongitudinally, passes in succession through all of the cores arrangedin the plane, at least one of the cores being thus positioned about atleast each turn of the helix, thereafter the wire is straightened,whereby the cores become positioned at the intersections of the wires,each of the cores being turned into a desired angular position.

In order to index the cores in a line of the matrix in perpendicularangular positions, it is advisable that the cores arranged into theplane intersecting the wires should be grouped into two rows spaced by adistance equal to the diameter of the helix into which the additionalthreading wire is wound, with the cores in one of the two rows beingstaggered in respect of the cores in the other one of said rows by ahalf of the pitch of the helix, whereby the cores in the different rowswill become indexed in the line of the matrix in perpendicular angularpositions.

In order to index the cores in the adjacent lines of the matrix inperpendicular angular positions, the adjacent lines should be threadedthrough with the additional wire being wound in helices of oppositedirections.

An apparatus for making ferrite matrices, wherein the wires with saidstacks of the ferrite cores received thereabout on a framework,comprises, in accordance with the present invention, a core feedingmember having at least one longitudinal guide adapted to take singleones of the cores and arrange them into a row, the core feeding memberhaving the wires with said stacks of the cores passing thereover at oneside thereof, the wires being spaced along the core feeding member atuniform intervals equalling the pitch of the threading helix; at leastone mechanism for winding the additional wire into the helix, associatedwith a drive and mounted adjacent to the face end of the core feedingmember, the mechanism winding the additional line threading wire into ahelix having a pitch equal to the spacing between the centers of the thecores arranged into the row by said core feeding member, there beingmounted parallel to said core feeding member an auxiliary rollercontacting the helix, the auxiliary roller having a plurality of annulargrooves spaced at uniformed intervals equalling the pitch of the helix,the auxiliary roller being mounted so that the grooves are staggeredfrom the centers of cores by a distance corresponding to the helix angleof the helix, the auxiliary roller being associated with drive so as tobe rotated thereby in the direction opposite to the direction of thewinding of the helix.

Preferably, the core feeding member is made in the form of a rollerhaving a plurality of spaced reduceddiameter portions, the spacing beingequal to the pitch of the helix, the longitudinal guides for supportingthe cores being provided in one plane both at the bottoms of thereduced-diameter portions and in the shoulders therebetween, whereby thecores supported thereby are positioned in two rows spaced by a distancecorresponding to the diameter of the threading helix.

The apparatus may comprise a second core feeding member having alongitudinal guide extending parallel to the first-mentioned corefeeding member, the re spective longitudinal guides of the core feedingmembers facing each other, the wires with the cores received thereaboutbeing arranged in two arrays and passing over the two core feedingmembers on the internal side thereof, so that the cores are supported inthe respective longitudinal guides in two rows spaced by a distancecoresponding to the diameter of the threading helix, with the cores inone of the rows being staggered relative to the cores in the other oneof the rows by one half of the pitch of the helix.

The apparatus may further comprise grippers mounted in opposition toeach the core supported in the longitudinal guide of the core feedingmember, the grippers being associated with actuators for displacingselectively the cores into a second row. The grippers may be associatedwith mechanisms for selectively either returning the cores supported inthe guides of the core feeding member back into the respective stacks,or displacing said cores beyond the second row.

It is alternatively advisable that the core feeding member should bedivided longitudinally into a plurality of sections, each of thesections having at least two of the longitudinal guides and beingassociated with an independent drive adapted to move the sectionsselectively, to bring the longitudinal guides of the different ones ofthe sections into alignment.

Preferably, the mechanism for winding the additional wire into the helixincludes a spindle with a cleft in one end thereof, adapted to retainthe wire, a sleeve having a thread of the same direction and pitch, asthe helix, the sleeve receiving the spindle thereinside, a retainingmember selectively coupling the sleeve with the spindle, and ahelix-forming member of a split structure, including die-tapsspring-urged to the tapering portion of said helix and having a helicalgroove.

The mechanism for winding the additional wire into the helix maycomprise a second sleeve received about the first sleeve and having athread of the same pitch, as the first sleeve, but of the oppositedirection, and an additional retaining member selectively coupling saidsleeves, said helical groove in the die-taps being twodirectional.

The object is attained also in a ferrite cube made up from matricesproduced in accordance with the herein disclosed method, the cube beingin the form of a hollow plait in which the matrices arranged at bothsides of the cylindrical surface of the plait in alternating squares,the respective diagonal lines of the squares extending axially andtransversely of the plait, the coordinate wires of both directions alongorthogonally intersecting helical lines, the outgoing leads of thereadoutinhibition windings of the cube being distributed longitudinallyof the hollow plait.

The object of the invention is further attained in a ferrite cube madeup from matrices produced by the method in accordance with theinvention, the matrices overlying one another and being electricallyinterconnected, in which cube, according to the invention, the matricesare interconnectd at the border lines thereof by solid coordinate wiresextending throughout the cube.

The invention thus provides for introducing mechanization into thethreading process, for eliminating the mounting frames of ferritematrices and to reduce the number of soldered connections between thecoordinate wires, the length of the wires being maximal.

The invention minimizes the amount of manual labor involved, reduces thestrain of the operators eyes, reduces the dimensions of ferrite cubes,offers the possibility of testing the matrices and to make good anyfaults thereof directly in the process of making a matrix, eliminatesthe masks and soldering, brings automation and mechanization into themain operations of the threading process, improves the quality ferritecubes, steps up the productivity and improves labor conditions.

The above assets result in the reduced cost of the product.

One possible product of the apparatus according to the invention aferrite cube in the form of a hollow plait of which the walls areconstituted by the ferrite matrices provides ready access to the coresand improves the thermal duty of the cube in operation; furthermore,depending on the desired mode of assembling of the ferrite cube with theelectronic blocks it is associated with, the cube may be curvedlongitudinally into any desired configuration, which reducessubstantially the length ofthe conductors that are to be laid betweenthe cube and the electronic blocks, which reduces electrical losses andimproves the dynamic characteristics of the cube. The thermal duty isalso improved because the cores are arranged in one layer throughout theentire length of the plait-like cube, and any cooling medium can beeasily introduced into the internal space of such cube.

The other alternative product of the method is wherein the ferrite cubemade up from flat matrices overlying one another, with soldering ofthewires along the border lines of the matrices, may be produced withoutsuch soldering, with solid coordinate wire passing through all thematrices of the cube in a zig-zag fash- BRIEF DESCRIPTION OF THEDRAWINGS The present invention will be more clear from the descriptionof the embodiments thereof, with reference to the accompanying drawings,wherein:

FIG. 1(a) FIG. 1(w) show schematically various possible patterns of thearrangement of the cores and wires in ferrite matrices produced by anapparatus embodying the invention;

FIG. 2 is a schematic view of an apparatus for making ferrite matrices,embodying the invention;

FIG. 3 is the core feeding member of the apparatus, having spacedshoulders for arranging the cores in two rows, according to theinvention;

FIG. 4 is the apparatus with two parallel core feeding members formaking ferrite matrices where the adjacent cores are turned inperpendicular directions;

FIG. 5 is the apparatus for making ferrite matrices where any of thecores can be turned in perpendicular directions;

FIG. 6 is an apparatus with the core feeding member divided intosections with two longitudinal guides, ac-

cording to the invention, and a part of a ferrite matrix wherein thesecond threading wire passes from one line to another internally of thematrix;

FIG. 7 is a mechanism for winding the wire into a helix of onedirection, according to the invention;

FIG. 8 is another modification of the mechanism for winding the wireinto a helix, capable of making helices of either of the two directions;

FIG. 9 illustrates a ferrite memory cube in the form of a hollow plait,according to the invention;

FIG. 10 illustrates a ferrite cube wherein the connections between thematrices are effected with solid coordinate wires, according to theinvention;

FIG. 1 1 is a schematic diagram of an apparatus, illustrating a methodof making ferrite matrices, according to the invention;

FIG. 12 is a schematic diagram of an apparatus, illustrating the methodof making ferrite matrices with indexing of the adjacent cores in a linein perpendicular directions, in accordance with the invention; and

FIG. 13 illustrates the method of testing ferrite matrices, according tothe invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to thedrawings, an apparatus for making ferrite matrices comprises a framework1 supporting thereon, with the aid of strips 2 and 3, a plurality ofwires 4 receiving thereabout each a plurality of ferrite cores 5arranged in stacks 6, the number of the cores corresponding to thenumber of the lines in the ferrite matrices to be manufactured by theapparatus, or, alternatively, in a ferrite cube to be manufacturedthereby. The wires 4 are arranged in a side-by-side fashion, the numberof the wires being equal the number of the wires extending along therespective one of the two coordinates of the matrix to be made. Theframework 1 has further mounted thereon a rotatable core feeding member7 in the form of a roller with a longitudinal guide slot 8 adapted togrip the cores and to arrange them in a line, one core about therespective one of the wires.

The wires 4 are uniformly spaced along the core feeding member 7, thespacing being equal to the pitch ofa threading helix 9, the wires beingrun over one side of the member 7 under a slight tension.

Disposed adjacent to one face end of the core feeding member 7 is atleast one mechanism 10 for coiling up the wire effecting threadingthrough the cores in the direction of the second one of the twocoordinates, the wire being coiled, or wound into a helix with a pitchcorresponding to the spacing betwen the centers of the adjacent pairs ofthe cores 5 engaged by the feeding member 7. The wire coiling mechanism10 is associated with a drive 11. Extending parallel to the core feedingmember 7, on the side of the cores 5 arranged into the line to bethreaded through, is at least one rotatable auxiliary roller 12 adaptedto engage the helix 9 at spaced points along the entire extent thereoflongitudinally of the feeding member 7. The auxiliary roller 12 has madetherein a plurality of annular grooves 13 uniformly spacedlongitudinally of the roller 12, the spacing being equal to the pitch ofthe helix 9, the roller 12 being mounted so that the annular groovesthereof are longitudinally displaced in respect of the adjacent centersof the cores 5 by a distance corresponding to the helix angle of thehelix 9. Thus, the helix 9 is positioned intermediate of the feedingmember 7 and the annular grooves 13 of the auxiliary roller 12 so thatthe cores 5 arranged into a line by the feeding member 7 will findthemselves in the respective areas adjacent to the line along which thehelix 9 contacts the feeding member 7. The auxiliary roller 12 isassociated with a drive, e.g., with the same drive 11 associated withthe mechanism 10 for winding the helix 9, the condition being that theroller 12 will be rotated simultaneously with the rotation of the helix9 in a direction opposite to the direction of the winding of the helix9, and that the linear speed of the points of the roller 12 engaging thehelix 9 will be slightly greater than the linear speed of thecorresponding points of the helix 9.

In order to effect separation of single cores 5 from the respectivestacks 6 and arrangement of the cores into a line along the feedingmember 7, the latter is associated with a handle 14 by means of whichthe feeding member 7 can be rotated upwardly in respect of the framework1 into a position at which the longitudinal guiding slot 8 aligns itselfwith the bottommost cores 5 in the stacks 6, whereafter the feedingmember 7 can be rotated in the reverse direction, i.e., downwardly, intoa posiion where the line of the cores 5 engaged by the slot 8 isreleased by this slot.

To provide for possibility of threading the cores 5 into a matrixwherein the cores will be alternatingly angularly displaced relative toeach other through either within each line (FIG. lu) or in adjacentlines (FIG. 1m to q), the feeding member may have an alternativestructure, e.g., it may be in the form of a roller 15 (FIG. 3) having aplurality of reduced-diameter portions 16 spaced longitudinally of theroller 15, the spacing between the adjacent reduced-diameter portionsbeing equal to the pitch of the threading-through helix 9. In this case,the longitudinal slots 8 are cut both in the larger-diameter portions 17of the roller 15 and in the reduced-idameter portions 16 thereof, theslots 8 being aligned within a single plane. The distance between a slot8 in the larger-diameter portion 17 and a slot 8 in the reduced-diameterportion 16 corresponds to the diameter of the threading-through helix 9,as measured radially of the roller 15. Thus, the helix 9 coiled i asingle direction provides that cores 5 in the adjacent columns of amatrix are perpendicular to one another (FIG. lu). If the direction ofthe coiling of the helix 9 is alternated from one to the next successiveline, the adjacent cores 5 will be perpendicular to one anothher both inthe lines and columns of the matrix produced (FIG. 1m to q).

Alternatively, in order to produce matrices wherein the cores will berotated relative to one another in the above-described fashion, theherein disclosed apparatus may incorporate a pair of core-feedingmembers 7 and 7' (FIG. 4) mounted on the framework 1. In this case, thecore-feeding members 7 and 7' are both in the form of rollers providedwith longitudinal slots 8 and 8, respectively, the two rollers extendingparallel to each other and having their respective slots 8 and 8'normally facing each other. The wires 4 run over the members 7 and 7',entering the space intermediate of the two rollers, the wires 4 beingalternatingly arranged into two series above the respective ones of themembers 7 and 7', whereas beneath the members 7 and 7' the wires 4 runin a single parallel row, forming a matrix (see FIG. la and FIG. 1m toq). The wires 4 are uniformly spaced longitudinally of the respectivecorefeeding members 7 and 7', the spacing being equal to the pitch ofthe threadingthrough helix 9, each wire 4 engaging either one of the twocore-feeding members 7 and 7', being spaced from the adjacent wires 4engaging the other one of the members 7 and 7 through a distance equalto one half of the pitch of this helix 9. In this embodiment of theinvention, the cores separated from the stacks are arranged in therespective slots 8 and 8 into two rows 18, the rows being spaCed by adistance equal to the diameter of the helix 1 of the threading-throughwire.

Similarly to the previously described embodiment of the invention, thedirection of the coiling of the helix 9 determines the pattern of thecores in the matrix produced.

In order to provide the possibility of threading ferrite matrices withany desired angular position of any core at the intersection points ofthe coordinate wires (FIG. Is), the herein disclosed apparatus mayincorporate a plurality of grippers 19 (FIG. 5), each gripper beingdisposed in opposition to the respective one of the cores 5 held by thecorefeeding member 7. The grippers 19 are in the form of hooks that canengage the cores 5 in the area of the stacks 6. Each gripper 19 isassociated with an independent actuator 20, whereby any one of thegripper 19 can be actuated to engage the respective opposite core 5 inthe guiding slot 8 and to displace it into the second row 18 of thecores, i.e., to displace it through a distance equal to the diameter ofthe threading-through helix 9, with simultaneous displacement of thelast-mentioned core 5 through a half of the pitch of this helix 9.

To produce matrices intended for permanent memory deivces having astructure of the kind illustrated in FIG. It, the actuators 20 with thegrippers 19 are capable of displacing the cores 5 beyond the second row18.

In order to provide a possibility of threading a second wire through thecores in the rows of a matrix, the wire making cross passages 21 (FIG.6) within the matrix from one row into another, the core-feeding memberis made up from a series of individual sections 22, the number of thesections being equal to the number of the desired cross passages 21 plusone, each one of the sections 22 having two longitudinal guiding slots8. In this case, each section 22 of the core-feeding member isassociated with the individual actuating handle 14 by means of which thelongitudinal guiding slots 8 of the appropriate sections 22 can beselectively aligned.

The wire coiling mechanism 10 of the present invention, employed eitherfor production of large matrices manufactured simultaneously on severalsuch apparatus operating in parallel, with the threading-through wirebeing handed over from one apparatus to another, or else for threading asingle wire through a pair of adjacent lines, leaving an unbroken loopbetween the two lines, has to meet certain specific requirements. Inother words, the mechanism should provide for removing the helixtherefrom without the wire being severed. In most cases the wireemployed is a relatively thin copper wire in an insulation sheath whichshould be maintained intact. The operation of threading the wire intothe mechanism 10 and that of removing the wire therefrom should be assimple and as quick as possible. In order to meet this requirement, thewire coiling mechanism 10 incorporates a spindle 23 (FIG. 7) with aradial cleft 24 in the end face thereof for retaining the wire beingthreaded in. Tail end 25 of the spindle is received in a sleeve 26having a thread of which the direction and the pitch are, respectively,the same as those of the helix 9 to be formed. The threaded sleeve 26 isassociated with a retaining member 27 which ensures positive coupling ofthe sleeve with the spindle 23. The helixforming member is made up by apair of separate die taps 28 and 29 having an internal helical groovecorresponding to the helix 9 to be formed. The two die taps 28 and 29are resiliently biased toward the tapering pc riphery of the spindle 23by a pair ofleaf springs 30 fastened by screws 31 to a housing 32 of themechanism.

The spindle 23 is adapted to be driven by the drive 11 through a pulley33.

When it is desirable to facilitate changing of the direction of thehelix being formed, the mechanism 10 can have an alternative structure.

The sleeve 26 (FIG. 8) having a thread of one direction is received,together with the spindle 23 and the retaining member 27, within anothersleeve 34 having a helical thread of the opposite direction. The sleeves26 and 34 are coupled, e.g., by means of another retaining member 35. Inthis case, the internal helical thread of the die taps 28 and 29 istwo-directional; it should be remembered that the die taps 28 and 29 arein the form of those portions of the commonly-used thread-cutting dietaps, where the crests of the thread are full-size ones. The twodie-taps engage therebetween the spindle 23 from diametrically opposedsides and are spring-biased toward the spindle.

A description of several structures of unique ferrite memory cubes thatcan be manufactured with the aid of the herein disclosed apparatus isgiven hereinbelow.

To reduce electric losses, to improve the dynamic characteristics andthe heat transfer capacity, and to facilitate access to the cores, it isadvisable that the ferrite memory cube should be in the form of a hollowplait 36 (FIG. 9) of which the walls are formed by a plurality offerrite matrices 37. The matrices 37 of this cube" are disposed at twodiametrically opposed sides of the cylindrical periphery of the cube, inthe form of alternating squares. In the drawing, FIG. 9, border lines 38between the adjacent matrices are shown in dotted lines. The diagonallines of the matrix squares 37 extend axially and transversely of theplait 36, while coordinate wires 39 and 40 extending in the tworespective coordinate directions are disposed along a pair oforthogonally intersecting right-hand and left-hand helical lines. Theoutgoing leads of the readout and inhibition windings of each one of thematrices 37 are distributed longitudinally of the hollow plait. It isworth mentioning that the ferrite memory cube" in the form of the hereindisclosed plait 37 can be either flat-ended or deformed longitudinallyinto curves, to fit in the best possible way the actual arrangement ofthe corresponding units of a computer or similar device, with which thecube is to be associated.

It is also possible to produce a similar cube including matrices whereinthe number of the wires extending, respectively, in the two coordinatedirections, is non-uniform.

FIG. 10 of the appended drawings illustrates schematically theconnections of a ferrite cube made up by matrices 37 superimposed oneonto another and connected by soldering at points 42 where thecoordinate wires pass from one matrix into another. However, the hereindisclosed method and the apparatus performing same make it possible tomanufacture a memory ferrite cube of this kind having no solderedconnections in the areas 42 where the wires interconnect the matrices,but having continuous coordinate wires 39 and 40 of the two coordinatedirections interwoven throughout the cube.

Let us now explain the operation of the herein disclosed apparatus,describing at the same time the method according to the invention.

It can be seen from FIG. 11 which presents a schematic diagram of theapparatus and illustrates the essence of the herein disclosed methodthat the coordinate wires 4 extending in one of the two coordinatedirections are first threaded through ferrite cores 5 arranged intoseveral stacks 6, whereafter individual cores 5 are separated from thestacks 6 and arranged into a row 18, one core 5 being separated fromeach one of the stacks 6. The disposition of the cores 5 within the row18, with the cores lying in the common plane intersecting the wires 4,is determined by the pitch of the helix 9 into which the wire which isto be threaded through the cores along the other coordinate direction iscoiled. Therefore, the cores 5 are arranged into the row 18 so that thecores are uniformly spaced, the spacing being equal to the pitch of thehelix. After the wire coiled into the helix 9 has been threaded throughthe cores, the wire is straightened, whereby one line in the ferritematrix being manufactured is formed; there is also formed the coordinategrid including at least two wires, with the cores 5 being located at thepoints of intersection of the two wires, the axes of the cores 5 beingrotated in the same direction into a position where they extend at 45 inrespect of the wires.

Then the above-described operation is repeated, and the threadingthrough the cores 5 separated from the stacks 6 is carried on, line byline, in which way there is formed a ferrite matrix illustrated in FIG.11, where the cores 5 extend diagonally in the same direction (FIG. 1a).

To produce a ferrite matrix (FIG. 12) where every two adjacent cores 5within a single line will be perpendicular to each other, the cores 5separated from the respective stacks 6 are arranged in two rows 18. Thearrangement of the cores in the rows 18 is determined by the pitch anddiameter of the helix 9 into which the wire that is to be threadedthrough the cores 5 is coiled.

Consequently, the cores 5 are arranged into the rows 18 so that theywill be uniformly spaced within each row 18, the spacing being equal tothe pitch of the helix 9, with the cores in one of the two rows 18 beingstaggered through one half of the pitch of the helix 9 in respect of thecores 5 in the other row. The distance between the two rows 18corresponds to the diameter of the helix 9. The cores arranged in theabove-described manner are threaded through by rotating the helix 9 intowhich the wire is being coiled. The free end of the helix 9 passesthrough the openings in the cores 5 and thus the wire is threadedsuccessively through the cores. The spacing between the cores 5 ineither row 18 being equal to the pitch of the helix 9, and the distancebetween the two rows 18 being equal to the diameter of the helix 9, thethreading-through operation results in two cores 5 being received abouteach turn of the helix 9, one of which the helix 9 enters from above andthe other one of which the helix 9 enters from below, whereby, after thehelix 9 has been straightened to form a line in the ferrite matrix beingmanufactured,

every core 5 in the line is positioned at the intersection of therespective two coordinate wires and is perpendicular to the adjacentcores, as illustrated in FIG. 12.

It can be seen from the above description that the herein disclosedmethod and apparatus can be employed for manufacturing ferrite matricesfor decoders and logical circuits wherein it is essential that the cores5 will occupy different positions at the intersections of the coordinatewires within a single line, and that in various combinations. To attainthis, at the beginning of the operation of making a matrix theindividual cores or groups of cores that will be turned in one directionin the line-to-be are positioned into the first row, while the coresthat will be turned in the perpendicular direction at the intersectionsof the respective wires are positioned into the second row for theproduction of the same line.

Moreover, it is possible to manufacture matrices intended for permanentmemory devices, wherein it is essential that cores will be eitherpresent or absent at specified intersections of the coordinate wireswithin a line, in accordance with a desired pattern (FIG. 1:). In thiscase, at the beginning stage of the line-making operation only thosecores are left in the row 18 which correspond to the specified pattern.The rest of the cores 5 is positioned outside the line 18.

For the cores in each line of the matrix being produced to be turnedperpendicularly in respect of the cores in the acjacent lines (FIG. l,hto q), the cores 5 arranged into the successive rows 18 arealternatingly threaded through by right-hand and left-hand helices 9.Consequently, after the threading-through and straightening operations,the cores 5 at each adjacent pair of intersections of the coordinatewires in every two adjacent lines are turned in perpendiculardirections.

From the above disclosure it is now clear that the ferrite matricesproduced by the herein disclosed method and apparatus can have the corestherein arranged in accordance with a great variety of desired patterns(FIG. I), each one of the cores being threaded through by either two ormore wires extending in perpendicular directions.

Let us consider the operation of the apparatus for making ferritematrices, illustrated schematically in FIG. 2.

The wires 4 with the stacks 6 of cores 5 received thereabout are securedto the plates 2 supported on the framework 1.

The wires 4 are arranged to extend parallel to one another under aslight tension, and are passed about the core-feeding member 7, with thecore stacks 6 positioned above the member 7.

The core-feeding member 7 is then manually rotated with the handle 14,for the longitudinal guiding slot 8 to be aligned with the bottommostcores 5 in the respective stacks 6. Thereafter the core-feeding member 7is rotated in the opposite direction, whereby the longitudinal guidingslot 8 separates one core 5 from each stack 6, and the separated cores 5are subsequently arranged into a row 18.

Then the wire that is to be threaded through the cores 5 is coiled intothe helix 9, for which purpose the wire is first threaded into thecoiling mechanism 10. This is done by unscrewing the sleeve 26 (FIG. 7)from the housing 32 of the mechanism 10 into a position where the cleft24 off the spindle 23 is situated in the area of the initial (theextreme left) helical grooves of the die-taps 28 and 29. Then theretaining member 27 is operated to couple the spindle 23 with the sleeve26, and the end of the wire that is to be coiled into the helix 9 isinserted into the cleft 24. By screwing the sleeve 26 together with thespindle 23 coupled therewith into the housing 32, with the sleeve beingrotated in the direction of the coiling of the helix-to-be, the end ofthe wire is secured during the first revolution in the cleft 24 of thespindle 23, whereafter the continuing rotation results in the helixbeing formed about the tapering portion of the spindle 23 entering thespace between the die taps 28 and 29. The pitch and the direction of thehelical grooves of the two die taps corresponding to those of the threadof the sleeve 26, each turn of the helix 9 formed between the die taps28 and 29 finds itself in its own groove. After the sleeve 26 has beenscrewed completely into the housing 32 of the mechanism 10, theretaining member 27 is released, and the drive 11 (FIG. 2) is operatedto drive the spindle 23 (FIG. 7) via the pulley 33 in the samedirection. The helix is now being coiled in the space between the dietaps; the end of the wire leaves the cleft 24, and the continuous helix9 is fed out by the coiling mechanism 10. It takes now but to cut offthe leading end of the helix 9, that has been deformed by the cleft 24,and the helix is ready for threading through the cores (FIG. 2).

Simultaneously with the operation of coiling the helix 9, the auxiliaryroller 12 is rotated also by the drive 11 in the opposite direction atan angular speed at which the linear speed of the points of the roller12, that contact the helix 9, to be slightly higher than that of thecorresponding points of the helix 9.

The helix 9 rotates and at the same time progresses translatorily inengagement with the auxiliary roller 12 and with the core-feeding member7, the leading end off the helix 9 entering successively the openings inthe successive cores 5 from above, strictly at the centers of therespective openings, thanks to the provision of the guiding annulargrooves 13 in the auxiliary roller 12. Moreover, the interaction of theroller 12 with the helix 9 supplies additional rotation to the latter,which is required for compensation of the residual stresses in the helix9, brought about by the coiling operation, as well as for overcoming thefriction of the helix 9 against the core-feeding member 7, in which wayit is possible to thread the helix 9 through the cores 5 arranged into aline of a considerable length.

After the leading end of the helix 9 has passed through all the cores 5in the row, the helix 9 is severed at the outlet of the mechanism 10,and the auxiliary roller I2 is swung aside to clear the path ofthe helix9 supporting the cores 5 thereabout.

Then the core-feeding member 7 is rotated with the handle 14, for thecores 5 with the helical wire 9 passing therethrough to leave thelongitudinal guiding slot 8 of the member 7, whereafter the cores 5 arelowered along the respective wires 4. Then the wire coiled into thehelix 9 is straightened, whereby a coordinate wire grid is formed, withthe cores positioned at the intersections of the wires and turnedstrictly diagonally in the same direction in respect of the wires. Theoperation of forming a line of a ferrite matrix is thus completed.

For making the successive line in the matrix, the above operation isrepeated, starting with returning the auxiliary roller 12 into theoperating position thereof.

The operation of threading the helix through a line of a matrix may becompleted each time by the helix being severed; however, in cases whenit is necessary to bend back the same wire for threading through thesuccessive line, e.g., for making a readout-inhibition winding, or elseas part of producing matrices of a great capacity, when the wirethreaded through a line in one apparatus is to be handed over withoutbeing severed to another apparatus, so that the line might be continuedwith the same wire, the helix 9 can be removed from the mechanism 10without the necessity of severing the wire intermediate of the helix andthe supply spool (not shown) from which the wire is unwound.

So, to remove the ready helix together with a length of straight, i.e.,uncoiled wire, the sleeve 26 (FIG. 7) is screwed out, whereby thespindle 23 is withdrawn from the helix 9, and the latter can be easilyremoved from the now empty space between the die taps 28 and 29 of themechanism 10.

The second embodiment of the wire coiling mechanism 10 (FIG. 8) offers apossibility of coiling the wire into a helix either of the left-handdirection or of a right-hand direction, and that without anyreadjustment of the mechanism itself. Let us consider the operation ofthis mechanism, presuming that the first sleeve 26 (FIG. 8) is providedwith a right-hand thread, and the sleeve 34 is screwed into the housing32 of the mechanism 10 and is provided with a left-hand thread.

Then, in order to produce a right-hand helix, the retaining member 35 isreleased, and the wire is threaded into the mechanism in the mannerdescribed hereinabove in connection with the first embodiment (FIG. 7)of the Wire coiling mechanism 10.

When a left-hand helix is to be produced, the mechanism 10 (FIG. 8) hasthe wire threaded thereinto in the following way. First, both retainingmembers 27 and 35 are brought into their retaining positions. The drive,which in this case should be reversible, is operated to drive the entiremechanism via the pulley 33, the mechanism being positively coupled bythe retaining members 27 and 35. In this way the mechanism is rotated inthe right-hand direction and is thus unscrewed from the housing 32,until the cleft 24 of the spindle 23 is positioned adjacent to theinitial grooves of the helixforming die taps 28 and 29. The leading endof the wire is inserted into the cleft 24, and the drive is reversed tocoil a left-hand helix about the tapering portion of the spindle 23.When the mechanism is screwed back into the housing 32 as far as it willgo, the retaining member 27 is released, and the spindle 23 alone isrotated in the same direction (i.e., the left-hand direction). Now theleft-hand helix that is being continuously coiled about the taperingportion of the spindle 23 is fed out by this spindle of the mechanism10.

The ready helix 9 can be removed without the wire being severed in a waysimilar to that of removing a right-hand helix by the retaining members27 and 35 being operated into their retaining positions, and the drive11 being reversed. The spindle 23 is withdrawn from the helix into thedie taps, and the helix can be easily removed from the mechanism 10.

Let us consider now certain individual operations and their stages, whentheir order is somewhat different from the abovedescribed process ofmaking ferrite matrices (FIG. 10) by the herein disclosed apparatus, thedifference residing solely in the operations of threading the wir intothe mechanism 10 (FIG. 2), in the modifications of applying the corestacks 6 onto alternating wires, in arranging the cores into a pluralityof rows 18, in necessity of employing either a plurality of corefeedingmembers 7 or core-feeding members of a modified structure, or else inemployment of additional auxiliary mechanisms.

FIG. la the ferrite matrix shown is manufactured by the operationsimilar to that described hereinabove in connection with the operationof the apparatus illustrated in FIG. 2.

FIG. lb the ferrite matrix is produced by the operation, as in FIG. la,except that one mechanism 10 for coiling the wire into the helix 9 ismounted at each side of the core-feeding member 7, the operations ofthreading the wire into these two mechanisms being performedalternatingly, i.e., the wire is first threaded into the left-handmechanism 10, and then into the right-hand one, in which way the winding43 is formed.

FIG. 10 the ferrite matrix shown is made by steps described hereinabovein connection with FIG. 1b, except that after the matrix is made adigital winding 44 is formed by the wire loops at one side of the matrixbeing severed.

FIG. 1d this ferrite matrix is produced by an operation similar to thatdescribed in connection with FIG. la; additionally, a wire intended as areadout-inhibition winding 45 is threaded in by an operation similar tothat of making the winding 43 in FIG. lb, the cores 5 (FIG. 2) arrangedinto the row 18 being threaded through with two independent wires coiledinto two helices 9.

FIG. 1e the ferrite matrix is made by steps similar to those describedin connection with FIG. 10, except that at the initial stage of makingthis matrix each stack 6 (FIG. 2) of the cores is put about two straightwires.

FIG. 1f the operation is that described in connection with FIG. la; thereadout-inhibition winding 46 being formed at the beginning of thematrix-making process, the stacks 6 (FIG. 2) of the cores being threadedthrough with two wires each stack, one of the two wires, intended to bemade into the winding 47 (FIG. 1), being threaded successively throughall the stacks, the end portions of this wire forming loops 48 enteringtwo adjacent stacks from the same side; the number of the cores in eachstack being the number of the cores in the column of the matrix-to-be.

FIG. 13 the coordinate wires of the ferrite matrix shown are threadedthrough by the steps described in connection with FIG. 1a, and thewindings 49 and 50 are formed by the steps described in connection withFIGS. 1b and 1f.

FIG. 1h the ferrite matrix is made by the steps described in connectionwith FIG. 1a; when the odd lines of the matrix are made, the cores 5(FIG. 2) arranged into the row 18 are threaded through with the helix 9of one direction, while the even lines are threaded through with thehelix of the opposite direction.

FIG. 1i the ferrite matrix shown is made by the steps described itconnection with FIG. lb, and the second winding is threaded through bythe steps described in connection with FIG. 10.

FIG. 1 j the ferrite matrix is made by the steps described in connectionwith FIG. 1h, the readoutinhibition winding 51 being threaded through bythe steps similar to those described in connection with the winding 45,FIG. 1d.

FIG. lk the coordinate wires are threaded through by the steps describedin connection with FIG. lb, and the readout-inhibition winding 54 ismade by the steps described in connection with FIG. 1f.

FIG. ll the steps of threading through the coordinate wires are similarto those described in connection with FIG. 1b; the windings 52 and 53are threaded through by the steps described in connection with FIG. lg.

FIG. 1m the ferrite matrix shown is made by the steps described inconnection with FIG. 1a, the cores 5 (FIG. 4) to be threaded throughwith the helix 9 being arranged in two rows 18 by two core-feedingmembers 7, or else by one feeding member 15 (FIG. 3), or, alternatively,they are arranged by the core-feeding member 7 (FIG. 5) with the help ofthe grippers 19. In any case, the second wire, passing from one line toanother, is threaded through in the form of helices of oppositedirections.

FIG. 1n when this ferrite matrix is made, the cores are threaded throughby the steps described in connection with FIG. 1m hereinabove, and thereadoutinhibition winding 55 is threaded through by the steps describedin connection with FIG. lb.

FIG. 10 the operation of making this matrix is similar to that describedin connection with FIG. 1e and m.

FIG. 1p the ferrite matrix is made by the steps described in connectionwith FIG. 1f, the threading through and the arrangement of the coresinto the row being similar to those described in connection with FIG.1m.

FIG. lq when the ferrite matrix is made, the coordinate wires arethreaded through the cores by the steps described in connection withFIG. 1m, and the windings 56 and 57 are threaded through, as describedhereinabove in connection with FIG. lg.

FIG. 1r when the ferrite matrix shown is made, the coordinate wires arethreaded through by the steps described in connectin with FIG. lb; thewinding 58 is threaded through, as follows: the cores 5 (FIG. 6)arranged into the row 18 and threaded through with one helix 9 formingthe second coordinate wire are not removed from the sections 22; priorto threading the second helix therethrough, one section of thecore-feeding member 22 is turned about, whereby the lower longitudinalguiding slot 8 thereof is placed opposite the upper longitudinal guidingslots 8 of the other sections 22, whereafter one line is threadedthrough with the helix 9; then the abovementioned section 22 of thefeeding member is turned in the opposite direction for the opposinglongitudinal guiding slots to align, whereafter the cores 5 are threadedthrough once again. Then the sections 22 of the core-feeding members arerotated into a position where the cores with the wires threadedtherethrough slide down along the wires 4; then the wires are tightened,in which way there are produced two threaded-through lines of the matrixhaving three wires passing therethrough, with a butterfly pattern of thewinding 58.

FIG. 1s the coordinate wires are threaded through the cores of theferrite matrix shown in a sequence described hereinabove in connectionwith FIG. 1d, the apparatus being that illustrated in FIG. 5. The cores5 that are to be turned in a line in the opposite direction are arrangedinto the second row 18 with the help of the grippers 19 associated withthe actuators 20.

FIG. lt the cores of this matrix are threaded through in the apparatusillustrated in FIG. 5. The threading-through process is the onedescribed in connection with FIG. I a, except that those of the cores(FIG. 5) that are to be threaded through are retained in the row, whilethe rest of the cores are displaced to lie outside the row.

FIG. lu this ferrite matrix is made by the steps described in connectionwith FIG. 1m, but the direction of the helix threaded through the coresalong the second coordinate is not reversed from line to line.

FIG. 1v this ferrite matrix is made, as follows: the first two lines ofthe matrix are made by the steps described in connection with FIG. 1a;the two successive lines are made by the same steps, but the directionof the helix being threaded through is reversed.

FIG. 1w the process of threading through, when this matrix is beingmade, is similar to that described in connection with FIG. 11', exceptthat at the beginning of the operation each stack 6 (FIG. 2) is putabout two wires.

Described hereinabove was the operation of the herein disclosedapparatus for production of ferrite matrices, in connection with variousarrangements and patterns of the cores in the matrices, each core ineach matrix being threaded through either with two or with more than twowires.

Let us now consider the sequence of the operations and steps of theprocess of making a ferrite cube in the form of a plait 36 (FIG. 9) onthe apparatus for production of ferrite matrices, constructed inaccordance with the present invention.

The wires 4 (FIG. 2), of a length sufficient for making all the matricesof the cube to be, are put through the stacks 6 of the cores 5 of whichthe number is likewise sufficient for making all the ferrite matrices ofthe cube. Then the appropriate ones of the steps described hereinabovein connection with FIG. 1d, f, g, j, k, l, n, p, q, r, s are employedfor making the first matrix of the plait 36 (FIG. I), whereafter othersuccessive matrices are made; when the first matrix is made, there ispassed through the threaded-through row of the cores a reserve length ofa straight wire, sufficient for forming the second coordinate directionthroughout the plait 36. Then the plate 2 is displaced to the borderline separative the first matrix from the successive one, the wires 4not being severed.

Then the second matrix is made, the helices 9 for threading through thelines of this second matrix being coiled from the reserve length of thewire, left after the similar lines of the previous matrix have beenthreaded through, in the same sequence and in the same direction.Moreover, when the threading-through of each successive line of thesecond matrix is completed, the wire is taken up to reduce the gapbetween the two matrices, with the released lower right-hand corner ofthe preceding matrix coming close to the lower left-hand corner of thesuccessive one, in which way the cylindrical shape of the ferritecube-to-be is attained.

The ferrite cube (FIG. 10) is assembled from flat matrices overlying oneanother, with the aid of the apparatus shown in FIG. 2, withoutsoldering of the coordinate wires intermediate of the matrices, thewires being solid wires passing through the entire cube. The matricesmaking up the cube illustrated in FIG. 10 may have either one of thepatterns illustrated in FIG. 1.

The steps and operations of the process of making the cube illustratedin FIG. 10 are similar to those of the process of making the plait-likecube" 36 (FIG. 9), the only difference being that in the case of thecube shown in FIG. 10 the first line and the successive lines of thesecond matrix have threaded therethrough the end of the wires,respectively, of the last of the last but one, etc. of the lines of thepreceding matrix. When the threading through of one matrix 37 (FIG. 10)is completed, and the threading through of the successive matrix isstarted, the mechanisms 10 disposed at the opposite face ends of thecore-feeding member are alternated, in which way every successive matrixis threaded through from the side opposite to that from which thepreceding matrix was threaded through.

Thus, the present invention makes it possible to introduce mechanizationand automation into the process of threading ferrite matrices of greatcapacities, incorporating the tiniest ones of ferrite cores, and thatwith considerably cutting down the amount of soldered connections in aferrite cube.

Furthermore, the invention reduces to a great degree the strain of theoperatorss eyes, increases the productivity of labor, providespossibility of performing mechanized threading of a digital winding,with transition from one coordinate line into another within the matrixbeing made, offers the choice of any desired pattern of the angularpositions of the cores at the intersections of the coordinate wires,provides for introducing mechanization into the production of theferrite core matrices of permanent memory devices, reduces theelectrical losses, improves the dynamic characteristics and the heattransfer capacity of memory devices, facilitates access to the memoryelements in a ferrite cube made in accordance with the herein disclosedmethod, offers combining of the operations of making ferrite matricesand of checking-up the memory elements thereof and making good thefaults cuts down the time needed for performing the operations, improvesthe quality of the product and reduces its cost.

Moreover, the herein disclosed method makes it quite simple to check theelectric properties of the ferrite cores being threaded and thus toeliminate the faults of the matrices being made directly in the courseof the threading operation.

The testing of the electric properties and the elimination of the faultsincludes several operations that are performed simultaneously with theprocess of threading and is carried out, as follows hereinafter.

The wires 4 (FIG. 13) that pass through the stacks 6 of the cores 5,which latter act as a quite definite load applied to these conductorwires, are connected through a terminal device 59 and the wire-mountingstrip 2, acting as the common bus-bar, have sent thereto a test programof current pulses coming from a pulse generator 60, to each wire insuccession.

The cores having the helix 9 threaded therethrough are connected to areadout amplifier 61, with the aid of which check-up pulses are derivedfrom each core about the helix 9.

If a faulty core is detected in the row through which the helix 9 hasbeen threaded, the helix is removed, i.e., withdrawn from the threadedline, for instance, by reverse rotation of the helix. The faulty core isthen broken and thus put off the respective wire 4. The following core 5from the respective stack 6 on the wire 4 is forwarded to replace thefaulty one. Thereafter the row of the cores, in which the faulty corehas been replaced, is rethreaded with the helically wound wire 9, andthen it is tested once again. When no faulty cores are detected in thethreaded line, the following row is forwarded and threaded through.

To step up the quality of group measurement and to make the testingconditions resemble those of actual operation of a ferrite cube, theproperties of the cores may be alternatively tested with the aid of athird wire which, in the course of the threading operation, is alsowound into a helix and is threaded additionally through the coresarranged into the row 18. The rest of the testing and fault correctingoperations are in the lastmentioned case similar to those describedhereinabove.

What is claimed is:

l. A method of making ferrite matrices, comprising the steps of:threading a plurality of ferrite cores, the cores being arranged intostacks, each of the stacks being threaded about at least one wire, thenumber of the cores disposed on said at least one wire being equal tothe number of columns in a matrix which is to be made; arranging thestacks into an array in which the number of the stacks is equal to thenumber of the wires in the direction of one coordinate of the matrixwhich is to be made; separating one of the ferrite cores from each ofthe stacks; arranging the separated ferrite cores in a planeintersecting the wires; winding an additional wire into a helix;rotating the helix and simultaneously forwarding same; threading saidadditional wire wound into the helix through the ferrite cores in thedirection of a second coordinate of the matrix so that the leading endof the helix passes in succession through all of the ferrite coresarranged in the plane, whereby at least one of the ferrite cores isreceived about at least each turn of the helix; and straightening saidadditional wire wound into the helix, whereby the ferrite cores receivedthereabout become positioned at the intersections of the wires and saidadditional wire and each of the cores is turned into a desired angularposition.

2. A method as in claim 1, further including the step of arranging theferrite cores into two rows separated by a distance equal to thediameter of the helix so that every two ferrite cores within a row ofthe matrix is perpendicular to each other, the ferrite cores in eitherone of the rows being staggered in respect of the ferrite cores in theother one of the rows'by a half of the pitch of the helix.

3. A method as in claim 1, further including the steps of winding onerow of the matrix with said additional wire formed into a helix in onedirection and winding a successive row of the matrix with saidadditional wire formed into a helix of the opposite direction so as toindex the ferrite cores in adjacent rows of the matrix in perpendicularangular positions.

4. A method as in claim 2, further including the steps of winding onerow of the matrix with said additional wire formed into a helix in onedirection and winding a successive row of the matrix with saidadditional wire formed into a helix of the opposite direction so as toindex the ferrite cores in adjacent rows of the matrix in perpendicularangular positions.

1. A method of making ferrite matrices, comprising the steps of:threading a plurality of ferrite cores, the cores being arranged intostacks, each of the stacks being threaded about at least one wire, thenumber of the cores disposed on said at least one wire being equal tothe number of columns in a matrix which is to be made; arranging thestacks into an array in which the number of the stacks is equal to thenumber of the wires in the direction of one coordinate of the matrixwhich is to be made; separating one of the ferrite cores from each ofthe stacks; arranging the separated ferrite cores in a planeintersecting the wires; winding an additional wire into a helix;rotating the helix and simultaneously forwarding same; threading saidadditional wire wound into the helix through the ferrite cores in thedirection of a second coordinate of the matrix so that the leading endof the helix passes in succession through all of the ferrite coresarranged in the plane, whereby at least one of the ferrite cores isreceived about at least each turn of the helix; and straightening saidadditional wire wound into the helix, whereby the ferrite cores receivedthereabout become positioned at the intersections of the wires and saidadditional wire and each of the cores is turned into a desired angularposition.
 2. A method as in claim 1, further including the step ofarranging the ferrite cores into two rows separated by a distance equalto the diameter of the helix so that every two ferrite cores within arow of the matrix is perpendicular to each other, the ferrite cores ineither one of the rows being staggered in respect of the ferrite coresin the other one of the rows by a half of the pitch of the helix.
 3. Amethod as in claim 1, further including the steps of winding one row ofthe matrix with said additional wire formed into a helix in onedirection and winding a successive row of the matrix with saidadditional wire formed into a helix of the opposite direction so as toindex the ferrite cores in adjacent rows of the matrix in perpendicularangular positions.
 4. A method as in claim 2, further including thesteps of winding one row of the matrix with said additional wire formedinto a helix in one direction and winding a successive row of the matrixwith said additional wire formed into a helix of the opposite directionso as to index the ferrite cores in adjacent rows of the matrix inperpendicular angular positions.